The role of immunoglobulin in cerebrospinal fluid on the differential diagnosis of autoimmune encephalitis and viral encephalitis in children.

BACKGROUND: A case-control study was conducted to analyze the role of cerebrospinal fluid immunoglobulin in the differential diagnosis of autoimmune encephalitis and viral encephalitis in children. METHODS: One hundred and twenty patients with autoimmune encephalitis (AE) treated in our hospital from February 2021 to February 2022 were included as the observation group (AE group). 100 patients with viral encephalitis (VE group) were selected as the control group. The clinical data of all patients were collected and analyzed retrospectively. Immunoglobulin G (IgG) and immunoglobulin A (IgA)in cerebrospinal fluid of the two patients were measured by immune turbidimetry. Immunoglobulin M (IgM), and the diagnostic value of immunoglobulin in cerebrospinal fluid (CSF) in patients with AE was analyzed by receiver working curve (ROC). RESULTS: The level of IgG in the cerebrospinal fluid of the AE group was higher than that of the VE group, and the level of IgM was lower than that of the VE group, and the difference was statistically significant (P < 0.05). There was no significant difference in IgA levels between the two groups (P > 0.05). In terms of Magnetic Resonance (MR) features, the paraventricular, hippocampal, occipital and parietal lobes were more involved in AE patients, frontal and temporal lobes were more involved in VE patients, and paraventricular and occipital lobes were involved in MS. The proportion of bilateral extensive lesions in both groups was significantly higher than 50%. The proportions of patients in the AE group involving the lateral ventricle, insula, and parietal lobes were significantly higher than those in the VE group, and the proportions involving the basal ganglia, temporal lobes, and frontal lobes were significantly lower than those in the VE group, and the differences were statistically significant (All P < 0.05). The Area Under Curve (AUC) of IgG, IgA and IgM alone in the diagnosis of AE were 0.795(0.587-0.762), 0.602(0.502-0.631) and 0.627(0.534-0.708), respectively with the sensitivity values of 81.24% and 65.608, respectively and the specificity values of 65.08%, 57.54% and 75.01% respectively. The AUC of IgA + IgM in the diagnosis of AE was 0.733(0.617-0.849), and the sensitivity and specificity are 62.58% and 75.07% respectively. The AUC of IgA + IgG in the diagnosis of AE was 0.823(0.730-0.917), and the sensitivity and specificity were 81.24% and 67.54% respectively. The AUC of IgG + IgM in the diagnosis of AE was 0.886(0.814 ~ 0.958), and the sensitivity and specificity were 84.48% and 77.59% respectively. The AUC of IgA + IgM + IgG in the diagnosis of AE was 0.924 (0.868-0.981) with the sensitivity of 93.82%, and the specificity of 77.56%. CONCLUSION: The level of immunoglobulin in cerebrospinal fluid can be used as an effective reference index for the diagnosis of AE. The combined detection of IgA, IgM and IgG can improve the accuracy, sensitivity and specificity of AE.

The application value of cerebrospinal fluid immunoglobulin in tuberculous meningitis.

This article aims to study the value of cerebrospinal fluid (CSF) immunoglobulin in differential diagnosis, prediction, and prognosis of tuberculous meningitis (TBM). The clinical data of 65 patients with TBM in our hospital were collected, and 65 patients with cryptococcal meningitis (CM) were enrolled in 1:1 matching. Relevant data were collected for comparison. CSFs IgG [331.51 (164.85, 645.00) vs 129.00 (55.05, 251.00) ng/mL], IgM [22.38 (8.52, 40.18) vs 6.08 (2.19, 23.30) ng/mL], and IgA [64.11 (21.44, 115.48) vs 16.55 (4.76, 30.36) ng/mL] in the TBM group were higher than those in the CM group (P < 0.001). In the TBM group, after 24 weeks of treatment, the CSFs IgG, IgM, and IgA were significantly decreased, and the difference was statistically significant (P < 0.05). The predictive results of CSF immunoglobulin for TBM showed that IgG, IgM, and IgA all had some predictive value for TBM, and the combined predictive value of the three was the highest, with an area under the curve of 0.831 (95% CI: 0.774-0.881). Logistic regression analysis of CSF immunoglobulins and TBM prognosis showed that IgG [odds ratio (OR) = 4.796, 95% confidence interval (CI): 2.575-8.864], IgM (OR = 3.456, 95% CI: 2.757-5.754), and IgA (OR = 4.371, 95% CI: 2.731-5.856) were TBM risk factors for poor prognosis in patients. The levels of IgG, IgM, and IgA in CSF were positively correlated with the severity of cranial magnetic resonance imaging (MRI) in TBM patients (R2 = 0.542, F = 65.392, P < 0.05). CSFs IgG, IgM, and IgA can be used as a routine monitoring index for TBM patients, which has a certain reference value in differential diagnosis and efficacy evaluation. IMPORTANCE: In clinical practice, physicians can determine the physical conditions of patients based on the levels of cerebrospinal fluids (CSFs) IgG, IgM, and IgA. Higher levels of CSFs IgG, IgM, and IgA suggest more possibility of tuberculous meningitis and worse prognosis and magnetic resonance imaging manifestations.

Kappa Free Light Chains in the Context of Blood Contamination, and Other IgA- and IgM-Related Cerebrospinal Fluid Disease Pattern.

In this retrospective, monocentric cohort study, we tested if an intrathecal free light chain kappa (FLC-k) synthesis reflects not only an IgG but also IgA and IgM synthesis. We also analysed if FLC-k can help to distinguish between an inflammatory process and a blood contamination of cerebrospinal fluid (CSF). A total of 296 patient samples were identified and acquired from patients of the department of Neurology, University Medicine Greifswald (Germany). FLC-k were analysed in paired CSF and serum samples using the Siemens FLC-k kit. To determine an intrathecal FLC-k and immunoglobulin (Ig) A/-M-synthesis we analysed CSF/serum quotients in quotient diagrams, according to Reiber et al. Patient samples were grouped into three cohorts: cohort I (n = 41), intrathecal IgA and/or IgM synthesis; cohort II (n = 16), artificial blood contamination; and the control group (n = 239), no intrathecal immunoglobulin synthesis. None of the samples had intrathecal IgG synthesis, as evaluated with quotient diagrams or oligoclonal band analysis. In cohort I, 98% of patient samples presented an intrathecal synthesis of FLC-k. In cohort II, all patients lacked intrathecal FLC-k synthesis. In the control group, 6.5% presented an intrathecal synthesis of FLC-k. The data support the concept that an intrathecal FLC-k synthesis is independent of the antibody class produced. In patients with an artificial intrathecal Ig synthesis due to blood contamination, FLC-k synthesis is lacking. Thus, additional determination of FLC-k in quotient diagrams helps to discriminate an inflammatory process from a blood contamination of CSF.

Gut microbiota-specific IgA+ B cells traffic to the CNS in active multiple sclerosis.

Changes in gut microbiota composition and a diverse role of B cells have recently been implicated in multiple sclerosis (MS), a central nervous system (CNS) autoimmune disease. Immunoglobulin A (IgA) is a key regulator at the mucosal interface. However, whether gut microbiota shape IgA responses and what role IgA+ cells have in neuroinflammation are unknown. Here, we identify IgA-bound taxa in MS and show that IgA-producing cells specific for MS-associated taxa traffic to the inflamed CNS, resulting in a strong, compartmentalized IgA enrichment in active MS and other neuroinflammatory diseases. Unlike previously characterized polyreactive anti-commensal IgA responses, CNS IgA cross-reacts with surface structures on specific bacterial strains but not with brain tissue. These findings establish gut microbiota-specific IgA+ cells as a systemic mediator in MS and suggest a critical role of mucosal B cells during active neuroinflammation with broad implications for IgA as an informative biomarker and IgA-producing cells as an immune subset to harness for therapeutic interventions.

Alemtuzumab therapy changes immunoglobulin levels in peripheral blood and CSF.

OBJECTIVE: The use of alemtuzumab, a humanized monoclonal anti-CD52 antibody has changed the therapy of highly active relapsing-remitting MS (RRMS). Alemtuzumab infusion depletes most lymphocytes in peripheral blood, whereas differential recovery of immune cells, probably those with a less CNS-autoreactive phenotype, is supposed to underlie its long-lasting effects. To determine whether alemtuzumab significantly reduces immunoglobulin levels in blood and CSF of treated patients, we analyzed blood and CSF samples of 38 patients with MS treated with alemtuzumab regarding changes in immunoglobulin levels. METHODS: Blood and CSF samples of patients were collected at the beginning of alemtuzumab treatment and at 12, 24, and 36 months after the first administration of the drug. Specimens were analyzed regarding immunoglobulin concentrations in blood and CSF. RESULTS: We observed significant and dose-dependent reductions of immunoglobulin levels (IgG, IgM, and IgA) in serum and CSF 12 and 24 months following 2 courses of alemtuzumab. Patients with persistent or returning disease activity who were treated with a third course of alemtuzumab exhibited even further decrease in IgG levels compared with matched controls treated twice. Here, alemtuzumab-treated patients with IgG levels below the lower limits of normal were more susceptible to pneumonia, sinusitis, and otitis, whereas upper respiratory tract and urinary tract infections were not associated therewith. CONCLUSIONS: Our results suggest to monitor IgG levels for safety reasons in patients treated with alemtuzumab-in particular when additional treatment courses are required-and to consider preventive action in critical cases. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that for patients with RRMS alemtuzumab reduces immunoglobulin levels.

CSF parameters associated with early MRI activity in patients with MS.

Objective: To identify CSF parameters at diagnosis of clinically isolated syndrome (CIS) and MS that are associated with early inflammatory disease activity as measured by standardized cerebral MRI (cMRI). Methods: One hundred forty-nine patients with newly diagnosed CIS and MS were included in the retrospective study. cMRI at onset and after 12 months was analyzed for T2 and gadolinium-enhancing lesions. CSF was tested for oligoclonal bands and intrathecal synthesis of immunoglobulin G (IgG), A (IgA), and M (IgM) before initiation of disease-modifying therapy (DMT). In a subgroup of patients, CSF and serum samples were analyzed for sCD27, neurofilament light chain, and IgG subclasses 1 and 3. Association between CSF parameters and cMRI activity was investigated by univariable and multivariable regression analysis in all patients, DMT-treated patients, and untreated patients. Results: IgG index, sCD27 levels in CSF, and to a lesser extent IgM index were associated with the occurrence of new cMRI lesions. IgG index and sCD27 levels in CSF were highly correlated. In a multivariable analysis, IgG index and to a lesser extent IgM index together with DMT treatment status and gender were strongest predictors of future cMRI activity. Conclusions: CSF parameters such as IgG and IgM index are independently associated with future MRI activity and thus might be helpful to support early treatment decisions in patients newly diagnosed with CIS and MS.

Association of Intrathecal Immunoglobulin G Synthesis With Disability Worsening in Multiple Sclerosis.

Importance: Reliable biomarkers associated with disability worsening in multiple sclerosis (MS) are still needed. Objective: To determine a possible association of intrathecal IgG synthesis and early disability worsening as measured by Expanded Disability Status Scale (EDSS) scoring in patients with relapsing-remitting MS or clinically isolated syndrome. Design, Setting, and Participants: Cerebrospinal fluid measurements and clinical data from the observational longitudinal German national multiple sclerosis cohort were analyzed. Patients were recruited between August 2010 and November 2015 from 18 centers. Data analysis was completed from August 2018 to December 2018. Exposure: Patients were offered standard immunotherapies per national treatment guidelines. Main Outcomes and Measures: A possible association between intrathecal IgG synthesis and risk of EDSS worsening 4 years after study inclusion was tested as the primary end point by multivariable binomial regression analysis. Kaplan-Meier analysis with a log-rank test was used to assess the association of intrathecal IgG synthesis with the time to EDSS worsening. Associations between intrathecal IgM or IgA synthesis and other cerebrospinal fluid parameters and EDSS worsening were analyzed as exploratory end points. Data collection began before the hypotheses were formulated. Results: Of all 1376 patients in the German Competence Network of Multiple Sclerosis cohort, 703 patients were excluded owing to missing cerebrospinal fluid or EDSS data. Of the 673 included patients, 459 (68.2%) were women. The mean (SD) age at baseline was 34 (10) years. Intrathecal IgG synthesis was associated with a higher risk of EDSS worsening after 4 years (odds ratio, 2.02 [95% CI, 1.15-3.58]; P = .01), independent of the occurrence of relapses and disease-modifying therapy. Additionally, intrathecal IgG synthesis was associated with earlier EDSS worsening; 4 years after study entry, worsening occurred in 28.4% (95% CI, 22.7%-34.1%) and 18.1% (95% CI, 12.4%-23.9%) of patients with and without intrathecal IgG synthesis, respectively. No association of other routine cerebrospinal fluid parameters with EDSS worsening was found. Conclusions and Relevance: Patients with new diagnoses of relapsing-remitting multiple sclerosis or clinically isolated syndrome with intrathecal IgG synthesis had a higher risk of and shorter time to EDSS worsening across a 4-year period of follow-up. Intrathecal IgG synthesis is a potentially useful marker for disability worsening in patients with multiple sclerosis and may be useful for early treatment decisions.

Increased cerebrospinal fluid albumin and immunoglobulin A fractions forecast cortical atrophy and longitudinal functional deterioration in relapsing-remitting multiple sclerosis.

BACKGROUND: Currently, no unequivocal predictors of disease evolution exist in patients with multiple sclerosis (MS). Cortical atrophy measurements are, however, closely associated with cumulative disability. OBJECTIVE: Here, we aim to forecast longitudinal magnetic resonance imaging (MRI)-driven cortical atrophy and clinical disability from cerebrospinal fluid (CSF) markers. METHODS: We analyzed CSF fractions of albumin and immunoglobulins (Ig) A, G, and M and their CSF to serum quotients. RESULTS: Widespread atrophy was highly associated with increased baseline CSF concentrations and quotients of albumin and IgA. Patients with increased CSFIgA and CSFIgM showed higher functional disability at follow-up. CONCLUSION: CSF markers of blood-brain barrier integrity and specific immune response forecast emerging gray matter pathology and disease progression in MS.

Brain magnetic resonance imaging, cerebrospinal fluid, and autoantibody profile in 118 patients with neuropsychiatric lupus.

The objective of this study is to analyze clinical manifestations, features of imaging, and laboratory assessment of patients with neuropsychiatric SLE (NPSLE) for better diagnosis and outcome prediction. One hundred eighteen NPSLE patients admitted to the Anhui Provincial Hospital in Hefei, China, between January 2006 and December 2016 were enrolled and analyzed retrospectively. All patients fulfilled the American College of Rheumatology revised classification criteria for SLE. Patients with NPSLE fulfilled the American College of Rheumatology (ACR) nomenclature and case definitions. All NPSLE patients underwent neurological investigations including MRI of nervous system, electroencephalograms, or CSF examination as part of the diagnostic evaluation of nervous system involvement. All statistical analyses were performed. According to different types of data, different statistical methods were used to determine factors associated with abnormal MRI among NPSLE patients. Statistical significance was defined as P value < 0.05(two-tailed). Twelve different neurological manifestations of NPSLE patients were shown, in which headache was most common symptom (25.95%, 34/131), followed by seizures (25.19%, 33/131), cerebrovascular disease (18.32%, 24/131), psychosis (8.40%, 11/131), and others including mood disorder, cognitive dysfunction, plexopathy, cranial neuropathy, movement disorder, myelopathy, acute confusional state, and anxiety disorder. Thirteen patients have two neurological symptoms at the same time. Cerebrospinal fluid was assessed in 76 NPSLE patients, in which 29 patients had higher pressure of cerebrospinal fluid and 66 patients had abnormal immunoglobulin in cerebrospinal fluid, predominantly with an increase of IgG (84.21%, 64/76), followed by an increase of IgA (69.74%, 53/76), and IgM accounted for 47.74% (34/76). The MRI taken by 66.10% (78/118) patients have shown abnormal lesions and/or ischemic changes in the bilateral cerebral hemisphere, thalamus, pons, brainstem, and cerebellum. The abnormal changes in MRI were correlated with antiphospholipid antibody (APL) and C3 (P = 0.026 and 0.040, respectively). The most common clinical manifestation of NPSLE is headache, followed by seizures and cerebrovascular accident. The test of cerebrospinal fluid and MRI plays an important role in the assessment of NPSLE. The abnormal intracranial lesions were correlated with the level of anti-cardiolipin antibodies (ACL) and C3.

Intrathecal immunoglobulin synthesis in patients with symptomatic epilepsy and epilepsy of unknown etiology ('cryptogenic').

BACKGROUND AND PURPOSE: To compare the frequency of intrathecal immunoglobulin (Ig) synthesis in patients with symptomatic epilepsy and epilepsy of unknown etiology ('cryptogenic'). METHODS: Patients with epileptic (n = 301) and non-epileptic (n = 10) seizures were retrospectively screened for autochthonous intrathecal Ig synthesis and oligoclonal bands (OCBs) in the cerebrospinal fluid. RESULTS: Intrathecal IgG/OCBs were detected in 8% of patients with epilepsies of unknown etiology, 5% of patients with first seizures of unknown cause and 0-4% of patients with epilepsy due to brain tumors, cerebrovascular disease or other etiologies. Intrathecal IgG/OCBs were not seen in patients with psychogenic seizures. Identical OCBs in serum and cerebrospinal fluid were more common in all patient groups (10-40% depending on underlying etiology). CONCLUSIONS: Intrathecal IgG synthesis/OCBs were observed slightly more frequently in patients with 'cryptogenic' epilepsy and with first seizures of unknown etiology than in other patient groups. However, this remained an infrequent finding and thus we could not confirm humoral immunity as a leading disease mechanism in patients with epilepsy in general or with unknown etiology in particular.

Common and uncommon neurological manifestations of neuroborreliosis leading to hospitalization.

BACKGROUND: Neuroborreliosis represents a relevant infectious disease and can cause a variety of neurological manifestations. Different stages and syndromes are described and atypical symptoms can result in diagnostic delay or misdiagnosis. The aim of this retrospective study was to define the pivotal neurological deficits in patients with neuroborreliosis that were the reason for admission in a hospital. METHODS: We retrospectively evaluated data of patients with neuroborreliosis. Only patients who fulfilled the diagnostic criteria of an intrathecal antibody production against Borrelia burgdorferi were included in the study. RESULTS: Sixty-eight patients were identified with neuroborreliosis. Cranial nerve palsy was the most frequent deficit (50%) which caused admission to a hospital followed by painful radiculitis (25%), encephalitis (12%), myelitis (7%), and meningitis/headache (6%). In patients with a combination of deficits, back pain was the first symptom, followed by headache, and finally by cranial nerve palsy. Indeed, signs of meningitis were often found in patients with neuroborreliosis, but usually did not cause admission to a hospital. Unusual cases included patients with sudden onset paresis that were initially misdiagnosed as stroke and one patient with acute delirium. Cerebrospinal fluid (CSF) analysis revealed typical changes including elevated CSF cell count in all but one patient, a blood-CSF barrier dysfunction (87%), CSF oligoclonal bands (90%), and quantitative intrathecal synthesis of immunoglobulins (IgM in 74%, IgG in 47%, and IgA in 32% patients). Importantly, 6% of patients did not show Borrelia specific antibodies in the blood. CONCLUSION: In conclusion, the majority of patients presented with typical neurological deficits. However, unusual cases such as acute delirium indicate that neuroborreliosis has to be considered in a wide spectrum of neurological diseases. CSF analysis is essential for a reliable diagnosis of neuroborreliosis.

Upper reference limits for cerebrospinal fluid total protein and albumin quotient based on a large cohort of control patients: implications for increased clinical specificity.

BACKGROUND: Determination of cerebrospinal fluid (CSF) total protein (TP) as well as of CSF/serum albumin quotient (Qalb) is part of the routine CSF work-up. However, currently used upper reference limits (URL) are not well validated leading to over-reporting of blood-CSF barrier dysfunction in approximately 15% of patients without neurological disease. The objective of this study was to determine age-related URL for CSF TP and Qalb in a cohort of control patients. METHODS: A total of 332 paired CSF and serum samples of patients without objective clinical and paraclinical findings of a neurological disease were analyzed for CSF TP and Qalb. CSF TP was measured by spectrophotometry and albumin in CSF and serum by nephelometry. RESULTS: CSF TP concentration and Qalb significantly correlated with age. In subjects at the age of 18-70 years, median CSF TP ranged from 320 to 460 mg/L and URL defined as the 95th percentile were 530-690 mg/L. Median Qalb ranged from 4.1 to 6.1 and URL from 8.7 up to 11.0. For URL of Qalb we calculated the following formula: age/25+8. CONCLUSIONS: Age-dependent URL for CSF TP and Qalb are presented here in a large cohort of control patients. They are higher than those currently recommended and this probably explains why isolated blood-CSF barrier dysfunction has been apparently over-reported. These new URL might be considered in a future revision of CSF guidelines.

Role of Chlamydia in Multiple Sclerosis.

Chlamydia and antibodies to them were detected by serological, molecular biological, and culture methods in the sera and cerebrospinal fluid of patients with multiple sclerosis and in the reference groups of subjects without neurological diseases. Correlations between the agent presence in the biological fluids of patients and clinical characteristics of the disease were analyzed. C. pneumoniae were more incident in the biological liquids of patients with multiple sclerosis than in healthy volunteers. On the other hand, the incidence of the agent in the patients was not high and its presence did not correlate with the clinical manifestations. C. trachomatis was equally rare in the patients and volunteers. The studies indicated the existence of a group of patients infected by C. pneumoniae in the cohort of patients with multiple sclerosis, but the impact of this agent for the disease course remains unclear.

[Use of immunological and molecular biological methods to diagnose cerebral toxoplasmosis in HIV infection].

Cerebral toxoplasmosis is one of the leading causes of neurologic diseases with high mortality rates in patients with HIV infection. Invasion was difficult to diagnose for a number of objective reasons. The objective of the investigation was to determine the clinical sensitivity of different laboratory techniques as both a single study and their various combinations to verify the diagnosis of cerebral toxoplasmosis in HIV-infected patients. Blood and cerebrospinal fluid were tested in 51 patients with Stage 4B HIV infection (AIDS) with the verified diagnosis of cerebral toxoplasmosis. Separate determination of specific antibodies of IgG, IgM, IgA and toxoplasma DNA in the blood and cerebrospinal fluid was shown to have an insufficient clinical sensitivity (37.3-68.6%). The benefits of various combinations of immunological and molecular biological assays enhancing the diagnostic efficiency up to 76.5-96.1% are demonstrated.

Assessing cerebrospinal fluid abnormalities in neurosyphilis patients without human immunodeficiency virus infection.

Neurosyphilis (NS) caused by Treponema pallidum (T. pallidum) subspecies pallidum, can affect the central nervous system during any stage of the disease. To assess several laboratory parameters for NS diagnosis, we performed a case control study on 42 hospitalized NS patients negative for human immunodeficiency virus (HIV) and 40 syphilis/non-NS patients, excluding NS patients at Xiamen Zhongshan Hospital from June 2010 to June 2011. Multivariate logistic regression model showed that the cerebrospinal fluid white blood cell (CSF-WBC, P = 0.009) levels, the CSF-LDH (P = 0.006) levels, the albumin quotient (P = 0.009) and the IgA index (P = 0.042) were independently associated with high risk of NS. The receiver operator characteristic (ROC) curve analysis revealed that the optimal cut-offs were 10 × 106 cells/L for the CSF-WBC concentration, 19.3 U/L for the CSF lactate dehydrogenase (LDH) concentration, 7.08 for the albumin quotient, and 0.14 for the IgA index. Combining the CSF-WBC level, the CSF-LDH level, the albumin quotient and the IgA index increased the NS diagnosis sensitivity to 97.6%. T. pallidum particle agglutination (TPPA) index significantly correlated with the CSF-WBC (r = 0.453, P = 0.000), the IgA index (r = 0.446, P = 0.000), the albumin quotient (r = 0.262, P = 0.017), and the CSF-LDH (r = − 0.278, P = 0.012), respectively. In addition, there were correlations between the CSF-WBC and the IgA index (r = 0.329, P = 0.003), and between the CSF-WBC and the albumin quotient (r = 0.306, P = 0.005). Our results indicated that simultaneous testing of CSF-WBC levels, albumin quotient, IgA index and CSF-LDH can help predict the likelihood of NS in HIV-negative patients.

Evaluation of a microsphere-based immunofluorescence assay for the determination of Immunoglobulin A concentrations in cerebrospinal fluid of dogs.

The simultaneous increase of immunoglobulin A (IgA) in serum and cerebrospinal fluid (CSF) is a characteristic finding in dogs suffering from canine steroid-responsive meningitis-arteritis (SRMA). The study aimed at developing and evaluating a microsphere-based immunofluorescence assay (MIA) for the measurement of IgA, trying to fulfill the need of a quicker method using only small volumes of CSF. Microsphere beads were coated with goat-anti-dog IgA antibodies and bound IgA was detected by a mouse-anti-dog IgA antibody in combination with a PE-labeled goat-anti-mouse IgG. CSF from 44 dogs were tested for IgA and compared with an in-house utilized ELISA. Using clinical relevant reference ranges, the new method showed a good agreement (84.17%) with the ELISA. A method comparison revealed a moderate agreement only. These findings indicate that the MIA will not replace the ELISA, but it opens the possibility for further research with microsphere-based assays.

Extracellular hsp70 release in canine Steroid Responsive Meningitis-Arteritis.

The role of extracellular 70 kDa heat shock protein 70 (ehsp70) in central nervous system inflammation is vastly understudied, despite evidence supporting the ability to drive a pro-inflammatory state. We investigated the presence of ehsp70 in cerebrospinal fluid (CSF) and serum of dogs with Steroid Responsive Meningitis-Arteritis (SRMA), with the hypothesis that an ehsp70 response would occur, and might play a role in the pathogenesis of this disease. Samples from 30 dogs acutely affected with SRMA, and 30 dogs treated with corticosteroids and currently in clinical remission from SRMA were compared with normal dogs. Serum and CSF concentrations of ehsp70 were quantified using an enzyme-linked immunosorbent assay. An ehsp70 response occurred in the CSF of dogs with SRMA and this response was attenuated by corticosteroid treatment. There was no correlation between serum and CSF concentrations of ehsp70, supporting local production and release of ehsp70 and not simply leakage from serum. Dogs with SRMA thus represent a powerful spontaneous model by which to study the role of ehsp70 in CNS inflammation.

Determination of immunoglobulin A concentrations in the serum and cerebrospinal fluid of dogs: an estimation of its diagnostic value in canine steroid-responsive meningitis-arteritis.

Previous studies on canine steroid-responsive meningitis-arteritis (SRMA) suggested that elevation of immunoglobulin A (IgA) concentrations in both serum and cerebrospinal fluid (CSF) is specific for SRMA throughout the different disease stages. Recent studies however have raised concerns about the value of this test. The purpose of this study was to investigate the diagnostic value of IgA concentration testing in paired CSF and serum samples. IgA concentrations of 525 paired canine CSF and serum samples were evaluated. Samples were obtained from dogs with SRMA (n=311) and dogs with miscellaneous conditions (n=214) such as other central nervous system (CNS) inflammatory diseases (n=34), CNS tumours (n=46), idiopathic epilepsy (n=42), intervertebral disc disease (n=46) and non-CNS diseases (n=46). Serum IgA concentrations were significantly higher in dogs with untreated SRMA compared to those with other diseases. IgA CSF concentrations were significantly higher in dogs with SRMA compared to other disease categories, with the exception of inflammatory CNS disease. The sensitivity for IgA concentrations in serum and CSF was 91% with a specificity of 78%. Analysis of 525 paired samples confirmed that IgA concentrations were higher in dogs with SRMA. Calculation of the diagnostic value of IgA concentration confirmed that the test is highly sensitive for SRMA. Testing paired CSF and serum samples for IgA is still recommended for the diagnosis of suspected cases of SRMA.

Pathogenetic factors for excessive IgA production: Th2-dominated immune response in canine steroid-responsive meningitis-arteritis.

Canine steroid-responsive meningitis-arteritis (SRMA) is a systemic inflammatory disease with a predominant manifestation within the cervical meninges, increased immunoglobulin A (IgA) levels in serum and cerebrospinal fluid (CSF), and a shift of the B:T cell ratio towards a higher percentage of B cells. A Th2-dominated immune response associated with SRMA was therefore hypothesised. Pellets of peripheral blood mononuclear cells (PBMNCs) and CSF white blood cells (CSF WBCs) from dogs in the acute phase of SRMA (n=16) and under glucocorticoid treatment for SRMA (n=16) were investigated for interleukin (IL)-2, interferon (IFN)-γ, IL-4, IL-5 and IL-10 mRNA expression by means of reverse-transcriptase real-time polymerase chain reaction. Results were compared with those of dogs with other inflammatory (n=9) and neoplastic disorders (n=10) of the central nervous system. A tendency towards low levels of Th1 response related cytokines (IL-2, IFN-γ) and high IL-4 expression was observed indicating a Th2-skewed immune response. The pronounced IL-4 production may be an important pathogenetic factor for excessive IgA production in the acute phase of SRMA and for those cases under glucocorticoid treatment.

[Experience with multiplex nested PCR and fluorescent antibody tests in the diagnosis of acute central nervous system infections with herpes simplex virus type 1 and 2]. / Tapasztalatok a heveny központi idegrendszeri fertozések herpes simplex vírus-1/2 diagnosztikájában a multiplex nested PCR- és a fluoreszcens jelzésu antitestválasz-vizsgálat kombinációjával.

UNLABELLED: The specific diagnosis of herpes simplex virus type 1 and 2 infections has an extreme importance in acute infections of central nervous system due to both availability of specific antiviral therapy and the possible serious consequences of the disease. AIMS: Evaluation of the relevance and interpretation of the results of PCR and the specific antibody testing. METHODS: Home made multiplex nested herpes simplex virus PCR and immunofluorescent IgM, IgA, IgG antibody tests were carried out in a total of 474 cerebrospinal fluid and 555 serum samples of 396 patients with acute infection of the central nervous system between 1. January, 2003 and 31. December, 2009. RESULTS: The herpes simplex virus etiology was verified in 21% of 396 patients (82 patients, mean 12 cases per year): 26 were diagnosed by both methods (32%), 41 by PCR only (50%), 15 by the detection of intrathecal antibody production only (18%) (p<0.0001). HSV type1 or 2 DNA remained detectable in 35% of the samples drawn after the 30th day of the disease. These patients were all younger than two years of age. CONCLUSIONS: 1. PCR increased the ratio of verified herpes simplex virus etiology in acute central nervous infections. 2. Testing the specific antibody response cannot be ceased even in the availability of PCR. 3. Herpes simplex virus type 1 or 2 DNA might persist in central nervous system in spite of the specific antiviral therapy especially in the infants. 4. Herpes simplex virus PCR can be repeated if an early sample is negative or if it is suspected false positive. 5. There is a need for cooperation between clinicians and virologists in the appropriate interpretation of the results and in finding etiology.